BLOCK COPOLYMERIZATION INITIATED BY CE(IV)-POLY(ETHYLENE GLYCOL) REDOX SYSTEM - KINETICS AND CHARACTERIZATION

The kinetics of ceric ion-poly(ethylene glycol) (PEG, mol. wt 6000) redox-coupled-initiated polymerization of acrylonitrile (M), yielding a block copolymer of PEG and poly(acrylonitrile) (PAN) in aqueous sulphuric acid medium, has been investigated. The polymerization experiments were conducted in the dark under a nitrogen atmosphere in the temperature range 35-60 degrees. The polymerization was found to proceed without an induction period. The rate of monomer disappearance was found to be dependent on [M](2), [PEG] and independent of both [Ce(IV)] and [H+]. The rate of ceric ion disappearance was directly proportional to [Ce(IV)] and [H+] but independent of [M]. The FT-i.r. spectra of the block copolymer showed the presence of both PEG and PAN segments. The elemental analysis indicated the molar composition of PAN and PEG in the block copolymer to be 80:20.